This invention relates to a cervical dilator.
In the case of overdue delivery owing to an insufficient opening of the cervix which may be caused by insufficient rotation of the fetus' head or by abnormal delivery because of the fetus' size, steps must be taken to effect a delivery which will not injure the mother's body or the fetus by dilating the cervix artificially.
The present methods of dilating the cervix are generally as follows: Hegar's dilator, Bossi's dilator colpeurynter, half colpeurynter, folding type of colpeurynter, metreurynter, dilator of metal spring type, Bougie, and the method of inserting gauze into the cervix.
These methods, however, have little effect in dilating the cervix and are difficult in use. Accordingly, injury to the mother's body and to the fetus often occur.
For example, Bossi's dilator, and the dilator of the metal spring type are apt to injure the cervix of the mother's body. The structure of the colpeurynter and metreurynter types cause difficulty in inserting them into the uterus. In the use of these instruments, the position of the fetus is apt to be changed suddenly from the occipital position to the sacral position, thereby pressing against the fetus' head. Further, in the use of the colpeurynter, it is usual to expand the device by pouring water into it after it is inserted into the uterus and then to pull it by weight at the end of the tube. In this procedure, however, often the device slips off outside of the uterus and dilation of the cervix cannot then be obtained.